Strictly speaking, GRP-LS is a two-port laparoscopic surgery, but the first approach of the port is performed on the flank, with the abdominal wall lifted, using the open method. A 5 mm trocar is inserted into the umbilical fold using laparoscopic monitoring to create a laparoscopic port. For this reason, the puncture wound in the umbilical fossa is hardly noticeable in the early postoperative period. In the open method, it is difficult to place a 5 mm trocar on the umbilicus because the first approach must be performed with a small incision. One advantage of the lateral approach with GRP-LS is that the laparoscopic port of the umbilicus can be installed safely and easily.
The great advantage of GRP-LS is that it does not require the same advanced technical skills required for conventional LS. The surgical procedure of GRP-LS, performed by inserting multiple forceps into one port, is similar to SILS. However, a major difference between the two procedures is that the surgical field is approached with the forceps and endoscope from different directions; thus, the forceps can be better manipulated during GRP-LS compared to SILS. In addition, GRP-LS allows instruments such as forceps, needle holders, scissors, and electric scalpels, traditionally used in conventional open surgery, to be used in LS.
Even a novice can sufficiently operate the forceps if the surgeon has acquired the basic forceps techniques learned in open surgery; it is not necessary to learn the surgical technique of the pistol-type forceps used in conventional LS. The movement of the forceps is restricted when using a trocar; using the Lap Protector, however, allows surgical procedures to be carried out that would normally require multiple ports and a 15 mm incision (the same size as the wound of a 12 mm port).
The Lap Protector allows expansion of the abdominal wall port and provides sufficient space for performing multiple-forceps operations, manipulating a needle, and extracting excised material. The Lap Protector also protects the wound and helps stop bleeding. It is considered that the fact that the postoperative complication of subcutaneous bleeding in GRP-LS has almost disappeared as compared with G3P-LS is due to the use of Lap Protector and the reduction of the number of treatment ports to one.
Generally, a decrease in the number of ports is considered a disadvantage in surgical procedures; however, in GRP-LS, the endoscope and the forceps are situated in different directions than are used in SILS. During GRP-LS, a Lap Protector is used rather than a trocar, and the port can be used more effectively even though the abdominal wall incision is the same size; therefore, it is possible to use several forceps inserted into one port. Furthermore, since GRP-LS can be operated using forceps and needle holders that are familiar in laparotomy, difficult operations such as suture ligation and traction in LM can be easily performed.
G3P-LS, which is performed in cooperation with an assistant, helps to train an inexperienced surgeon, but once the surgeon becomes accustomed to the GRP-LS technique, which allows the use of multiple forceps in one port, the surgeon will not need an assistant. The superior ease of the GRP-LS technique compared to G3P-LS is why GRP-LS became the predominant method within three years of its introduction.
When the surgical results of GRP-LS for fibroids were compared with those of G3P-LS, it was observed that the weight and number of fibroids removed were the same with both techniques, but favorable results, such as a shortened operative time and reduced blood loss, were observed with GRP-LS.
An extracorporeal method was used for LC and LT procedures, in addition to intraperitoneal manipulation. In the extracorporeal method, the trocar is removed, and the ovaries and fallopian tubes are guided near the abdominal wall or outside the body to perform surgery with the naked eye without using an endoscope. With GLS, it is possible to perform extracorporeal surgery safely by adjusting the elevation of the abdominal wall. In terms of LC and LT results, GRP-LS showed a significant reduction in operative time and blood loss compared to G3P-LS, and no non-inferiority of GRP-LS was observed. Thus, it was clarified that GRP-LS is not only superior in abdominal wound but also in surgical results compared to G3P-LS.
GRP-LS had fewer instances (0.09%) where a transition to open surgery was required compared to G3P-LS (0.53%); this rate of transition to open surgery are very low compared to that of the pneumoperitoneum method (0.27%: 424/157,586 cases) 10.
The establishment of the GRP-LS technique reduced the need for a transition to open surgery due to technical difficulties; in addition, there are fewer complications because of the advantages GRP-LS provides for the manipulation of forceps; a simultaneous increase in the use of MRI increased the likelihood that malignant tumors could be discovered before surgery.
In this study, GRP-LS was performed by 78 surgeons and G3P-LS was performed by 93 surgeons, respectively. In GRP-LS, novice surgeons with fewer than 50 surgical experiences accounted for 85.9% of the total amount of surgeons in this category, which performed approximately half of the surgeries. In G3P-LS, surgeons with fewer than 50 surgical experiences accounted for 89.2% of the total amount of surgeons in this category, while the number of surgeons with less than 10 surgical experiences amounted to 57% of the total number of surgeons. It is speculated that these surgeons completed the surgery with the strong assistance of a skilled assistant. On the other hand, in GRP-LS, since it is a solo surgery in which a surgical procedure is performed without an assistant, it truly shows the ability of the surgeon himself. From this, it is shown that GRP-LS is a surgical method that is easy to learn for beginners in laparoscopic surgery.
Despite the fact that there is no bias in the average number of surgeries per surgeon among the groups of surgeons classified by the number of surgical experiences as a surgeon, the proportion of surgeries by surgeons with fewer than 20 surgical experiences decreased from 18.4–9.7% when GRP-LS and G3P-LS were compared, and conversely increased from 39.0–49.7% for surgeons with less than 50 surgical experiences. This means that the number of novice surgeons who continue to operate on GRP-LS has increased, and it is a factor in the facilitation to the introduction of GRP-LS. Moreover, the overall results including the low rate of complication rates and no transition to open surgery in GRP-LS this time are showing that it can easily be achieved by senior surgeons as well as many beginners.
In obese patients, surgeons performing GLS find it difficult to establish a good operative field 6. Generally, in severely obese cases, the abdominal wall is thick, so even if the abdominal wall is lifted, the fat in the abdominal wall hangs down and a good operative field is often not obtained. However, in this study, the effect was hardly observed. This is thought to be due to the fact that the average BMI of Japanese women is 22.6 11 (In this study, 0.1% of cases had a BMI of 35 or higher), which is very low compared to Westerners 12, 13.
In patients with a BMI of less than 35, we overcame this challenge by placing the patient at an angle and raising the pelvic height (a 30-degree Trendelenburg position). In patients with a BMI above 35 degrees, we combine GLS and pneumoperitoneum using EZ Access® (Hakko Co., Ltd.) 14. In this case, the intra-abdominal pressure of the pneumoperitoneum can be suppressed by being combined with GLS, and we would like to further examine the usefulness of this hybrid method for severely obese patients by looking at variables such as pneumoperitoneum pressure, Trendelenburg position angle, and the number and position of ports.